Practical and comprehensive guidelines for bedside cerebral hemometabolic multitherapeutic optimization

Abstract

-In recent years, noncomprehensive "guidelines" were proposed for the management of severe acute brain injuries, focusing strictly on two approaches: 1) to maintain cerebral perfusion pressure anywhere above 70 mm Hg; and 2) to maintain arterial carbon dioxide tension levels above 30 torr. Strictly following these propositions, a recently reported prospective controlled study addressed mortality rates of no less than 75-76%, far worse than mortality rates reported before those "guidelines" were published. As a humanitarian alternative, the present comprehensive guidelines are aimed at addressing practical bedside strategies to manage no only intracranial pressure and cerebral perfusion pressure but also cerebral extraction of oxygen, based on solid previously reported papers which revealed the lowest mortality rates (below 15%) in the pertinent literature, in recent years.KEY WORDS: cerebral extraction of oxygen, intracranial pressure, guidelines, head injury.Diretrizes práticas e abrangentes para otimização hemometabólica cerebral multiterapêutica Diretrizes práticas e abrangentes para otimização hemometabólica cerebral multiterapêutica Diretrizes práticas e abrangentes para otimização hemometabólica cerebral multiterapêutica Diretrizes práticas e abrangentes para otimização hemometabólica cerebral multiterapêutica Diretrizes práticas e abrangentes para otimização hemometabólica cerebral multiterapêutica RESUMO -Em anos recentes, "diretrizes" não abrangentes foram propostas para o tratamento de traumatismos cerebrais agudos graves, enfocando estritamente em duas abordagens: 1) manter-se a pressão de perfusão cerebral em quaisquer níveis acima de 70 mm Hg; e 2) manter-se a pressão parcial de gás carbônico arterial acima de 30 torr. Seguindo estritamente tais proposições, artigo recentemente publicado envolvendo estudo prospectivo controlado revelou taxas de mortalidade de não menos que 75-76%, muitissímo piores do que taxas de mortalidade publicadas anteriormente a essas "diretrizes". Como uma alternativa humanitária, as diretrizes aqui propostas têm como meta explicar estrategias para que se tratem não apenas a pressão intracraniana e a pressão de perfusão cerebral, mas também a extração cerebral de oxigênio, baseando-se em trabalhos sólidos publicados anteriormente, os quais revelaram as menores taxas de mortalidade (inferiores a 15%) da literatura pertinente, em anos recentes. PALAVRAS-CHAVE: extração cerebral de oxigênio, pressão intracraniana, diretrizes, traumatismo cerebral.Back in 1996, "guidelines" for the management of severe acute brain injuries were published by several authors and were said to be "evidence-based"1 . This was not true, however, because no less than four strictly relevant previously published papers 2-5 were omitted from citation and discussion in those "guidelines", despite the fact that those four papers had been published in leading international medical journals. Therefore, those "guidelines" 1 were biased and not truly evidence-based, as would have been required in a pub...

Cerebral hemodynamic changes gauged by transcranial Doppler ultrasonography in patients with posttraumatic brain swelling treated by surgical decompression

“…When nonsurgical management fails to control ICP and cerebral herniation, decompressive craniectomy may be indicated as a last resort. 4,7,13 Despite many publications on the subject, 2,6,9,12,14,17,24,34,36,39,43,44,49,52,55 the actual benefit of this treatment modality on neurological outcome in patients remains unknown. The hemodynamic changes in the brain in response to decompressive craniectomy have not been systematically studied in patients with traumatic brain swelling.…”

“…Therefore, performing decompressive craniectomy as the sole treatment is insufficient. Even during postoperative phases, all efforts must be made to maintain adequate brain hemodynamics, 32,46 preferably coupled with brain metabolism 7,8 as well as to promoting pharmacological brain protection and regeneration so that some degree of brain recovery can be possible. For the future, we hope that routine TCD monitoring of both cerebral autoregulation and cerebral vasomotor reactivity may help in offering adequate intracranial hemodynamics, and consequently, adequate CBF to brain-injured patients.…”

Hemodynamic and metabolic parameters in brain injury

“…Based on our data, we can observe mean intracranial pressures greater than 20 mmHg during the clinical outcome of adult and pediatric patients ( Table 3 and 4). Mean ICP in children was higher on the first days following TBI, dropping thereafter.…”

“…Adelson et al suggest that a CPP of 50-65 mmHg is appropriate for the pediatric group and that a CPP less than 40 mmHg is consistently associated with an increase in mortality 2 . In the pediatric group, mean CPP was 40 mmHg and mean ICP amounted to 32 mmHg, whereas in adults, mean CPP was 52 mmHg and mean ICP was 31 mmHg (Table 3 and 4). Although the pediatric group had a slightly higher mean ICP and a lower mean CPP, mortality was higher among adult patients.…”

“…Hypercarbia increases intracranial pressure, whereas hypocarbia has the opposite effect; desirable PaCO 2 levels are around 32 mmHg, but a PaCO 2 less than 28 mmHg should be avoided during hyperventilation, especially on the first day of trauma, unless other therapeutic measures have failed 16 . Cruz recommends a PaCO 2 of 20-30 mmHg for 3-4 days until hyperventilation is optimized 4 . This author also points out the necessity for gradual stabilization of PaCO 2 at 30 mmHg when the patient's ICP levels tend to normalize and after at least 4 days.…”